Air gauge head



ug- 10, 1965 w. A. MlNlx 3,199,201

AIR GAUGE HEAD Filed Got. 50. 1963 I N VENTOR. 0M l/JM A. MM//X A frans/ United States Patent O The present invention relates to an air gauge for controlling air bleeding in a pneumatic measuring circuit.

This invention is an improvement over the air gauge head dened in my co-pending application No. 294,024, led luly lO, 1953, now Patent 3,147,615.

l-leretotore, various types of air gauges or gauge heads have been employed in circuits of this nature for the purpose of responding to the surface of the work piece for checking the dimensions thereof and wherein the defiection of the gauge element in responding to the surface of the work piece permits the bleeding of air through the sauge device in turn effecting the flow of air in a measuring circuit to give visible indication as to whether the worl; piece meets or does not meet a predetermined standard "mensicn within a predetermined range. One of the dirnculties ot air gauges of this type `nas been the eX- cessive wastage of air through the gauge body when the gauge head is not in use.

lt is therefore an object of this invention to provide an automatic shut-oit valve within the air gauge so that air does not flow through the gauge body when the gauge is not in use. ln the present construction air ilows only when the gauge head is being used.

These and other objects will be seen from the following specification and claims in coniunction with the appended drawing in which:

l is a partly sectioned schematic view illustrating the present air gauge head as mounted in a fixture and used in conjunction with a pneumatic measuring air flow circuit.

2 is a longitudinal section of the air gauge head on an increased scale.

WQ. 3 is a fragmentary section taken in the direction i -ta of arrows 3 3 of 2.

it will be understood that the above drawing illus* trates merely a preferred embodiment of the invention, and that other embodiments are contemplated within the scope @t the claims hereafter set forth.

Pr EUMATIC MEASURENG ClRCUlT The present air gauge is employed in connection with a pneumatic air flow measuring circuit. In FIG. l, a pair of the present air gauge heads il are mounted Within blocks 212 land 13 of xture F and secured at i4 in diametrically opnosed relation, and between which work piece W is proiected for gauging purposes.

The pneumatic measuring circuit includes an air flow gauge assembly generally indicated at l5 including valve body ld, tube support i7 with glass dow tube l interposed, within which the iioat i9 is movably positioned depending upon the rate of how of air therethrough. A sul'ahle indicating scale 2@ is provided.

Air from a suitable source is directed through pressure atcr 2i for el tcl .ivering air under pressure, such as at to twelve pounds per scuare inch, through conduit 22 to int-alte chamber 23 of the valve body. The air passes upwardly through tube l, through support l? and conduit 24 returning to delivery chamber 2S in the valve body, and thence through flexible plastic or other conduit 26 connected over inlet 33, FIG. 2, of one of the gauging beads il, FlG. l.

Associated with intake chamber 23 is a by-pass valve 27 adjustably mounted Within valve body 16 for the purpose et lay-passing some or the air from the intake chainer directly to delivery chamber rather than through Patented Aug'. lil, lgi

the glass tube T13. This is for the purpose of regulating the magniiication factor ot the air measuring system,

Fthere is also provided concentrically with the by-pass valve a bleed valve 2S which controls the release of some of the air within delivery chamber 25 through passage 29 directly to atmosphere. This is an air bleed for adjusting oat 19 within tube l under certain conditions and with a predetermined initial delivery pressure from regulator 2l.

lThe detail of the construction and operation of said pneumatic measuring air ilow circuit is more fully disclosed in my presently copending patent lisation executed June 7, 1963, Serial No. 290,526, tiled iune 25, 1963, now Patent 3,170,318.

AlR GAUGE HEAD The present invention is particularly directed to the construction of the air gauge head il, which is shown in fixture F for gauging purposes in FIG. 1, one of said gauge heads being indicated in detail in FIG. 2.

AIR GAUGE BODY rThe air gauge head lll includes elongated body Sie having an axial bore 3l and communicating therewith a series Kof transverse air outlets 3l', said bore having a threaded portion 32 towards one end. The body includes at its opposite end an elongated air inlet 33 with axial internal bore 37.

Within the outer end of said inlet there is an economizer orice, preferably constructed of brass, including body 36 snugly pressed within bore 37. Said body has an axial orifice or passage 3S by which air from tube 2d is directed into inlet 33.

BEARING NUT The threaded shank 3d of bearing nut 35 engages the threaded portion 32 of bore 3l, and the headed end portion of said nut engages the end of the body as at dd, FIG. 2.

Within the inner end of inlet 33 and adjacent bore Sil, there is press Iitted an intalre bearing 39 of cylindrical shape. Bearing 39 has a central or cylindrical bore tl-2, and at one end the enlarged annular head 4@ which engages shoulder 4l at the inner end of inlet 33 and relative to bore 3l. The hollow open ended bearing nut 35 has an axial bore t3 which communicates with the interior bore or chamber 3l of the body.

STEM

The control mechanism of the present guage head is the elongated axial stern generally indicated at 4S which includes head having a hemispherical reces-s d'7 in its outer end. Within said recess is nested `and fixedly secured the preferably carbide ball d3, also shown in PEG. l, adapted for operative engagement with the surface of work piece W Whose dimension is to be gauged.

The head di? terminates in shoulder d@ which serves as a positive stop limiting inward movement of the stern with respect to the gauge body. Said shoulder merges With shank portion 5@ or" cylindrical shape which is slidably and guidably positioned within bore 5:-3 of bearing nut 35.

AUTOMATC AER SHUT-OFF VALVE INCORFQRATED INT@ STEM The stem at its inner end includes as an extension thereof an axially movable spring-biased normally closed automatic air shut-oit valve 5d. Said valve is of cylinrical shape, normally nested within bore d2 of air inlet bearing 39 and closes oil ow of air from inlet 33 through bearing 39 and into bore 3l.

Exterior surface portions of valve body 56 have a series ot elongated utes S2 formed therein which are ot decreasing radial depth towards the inner end of the valve E body and run out, to the outer annular surface thereof, .as at 55, FIG. 2.

Valve 56 is adapted for unseating movement outwardly of air inlet bearing 39 upon inward movement of stein i5 relative to said body. This permits the ilow of air from inlet 33, through the ser-ies of radiallyand outwardly directed flutes 52 into bore 3i for release through radial outlets 3l under the control of Valve element 53.

Ain rLow ConTnoLvALvn ELEMENT The cylindrical body portion 50 of stem i5 terminates in the reduced cylindrical extension d which in turn terminates in the 'annular outwardly and forwardly tapered ow control valve 'element 53 forming a part of the stern and .arranged inwardly of shutoft valve 56. The flow control valve S3 in the inoperative position of the stern shown in FIG. 2 is spaced axially forward of air inlet bearing Si?. v

Upon initial application of' stem d5 with work W causing said stem to move inwardly, the tapered air control valve element S3 moves inwardly relative to the outlet end of bore .2 in air inlet bearing 39. This variably regulates the flow of air therethrough. On suliicient inward movement of stern i5 the cylindrical portion 5d will completely close off the ow of air through inlet bearing 39.

STEM ANE) AlR INLET'VALVE BIASING ASSEMBLY f Annular stop collar 57 is mounted over cylindrical portion titl of stem 45 and is retained against movement in one direction by snap ring 53, which is nested within an annular groove formed in stem portion Sti. The coiled the inlet bearing and into chamber 3l for exhausting through outlets 3i.

The quantity lof air which will iiow through bearing 39 is thereafter regulated bythe positioning of the tapered valve element 53 relativeito the ,outlet end of bearing 39 to thus variably regulate the flow of air through the gauge head and thence to atmosphere.

The automatic shut-off valve 56 normally does not eliect the operation yof the air gauge itself since it merely closes off the flow of air through the gauge body when the gauge :is not in use. Once the stem t5 has been lactivated by work piece W, PlG. 1, and is projected inwardly, the shut-od valve 5d is unseated as at 55, FG. 2, and thereafter the control of air flow through the body and particularly through air intake bearing 39 is regulated by the annular outwardly tapered valve element S3.

lt is thelongitudinal positioning lof this valve element 53, FG, 2, which variably regulates the rate of air ilow spring 59 extends axiallyraround the s-tem within bore 3l, Y

at one end engages stop collar 57 and its opposite end bears against the end wall of the body adjacent one end of bore 3l, adjacent and concentric to air inlet bearing 39.

The ring 5S serves an additional function of limiting outward disassembly movement of stem i5 relative to the l work piece.

(2) The coiled spring 59 serves the further function in biasing the stem outwardly so as to maintain the air control Valve 56, normally seated or nested snugly but slidably within bore t2 of air inlet bearing 39. This cuts ofi the flow of air from inlet 33 into bore 3l when the valve head is not in use in a gauging .operation such as in the position shown in FG. 2.

When the gauge head is placed into operation FIG. l, and the stem 50 moved inwardly from the position shown in FIG. 2, just as soon as valve 56 has been moved inwardly sufciently so that the run out end portions 55 of iiutes 52 are uncovered and extend outwardly of air inlet bearing 39, .air may then ow from inlet 33 through through the gauge body and `out through apertures 31 in turn modifying the air fiow inV the'measuring circuit l5 of FlG. l.

Having described my invention, reference should now be had to the following claims.

I claim: il. ln an air gauge for controlling air bleeding in pneumatic measuring circuit and including an elongated body having a bore, radial air outlets communicating with the bore and an -elougated air inlet; a cylindrical air inlet bearing in said inlet communicating with said bore;y a hollow open ended bearing nut projected `into said bore iat 'and engaging one end of the body; a work piece engaging stem axially mounted within the body and adjacent its opposite ends guidably, slidably and axially journalled respectively in said intake bearing and said bearing nut; the improvementcomprising: an axially movable spring biased normally closed automatic air shut-oit valve of cylindrical shape snugly and slidably positioned within said air inlet bearing and joined to said stem, surface portions of said valve having a series of elongated flutes communicating with the inlet bearing, bore, said valve adapted for unseating movement outwardly of said inlet bearing upon inward movement of said stem relative to said body, permitting flow of air from said inlet, through said flutes and into said bore; and an annular outwardly and forwardly tapered flow control valve element on said stem inwardly of said air shut-oit valve movable into said inlet bearing for variably regulating the rate of air ilow therethrough. 2. ln the air gauge defined in claim l, the inner ends of said flutes running out to the outer surface of said valve and communicating with said inlet after initial inward movement 'of said stem.

References Qited by the Examiner ISAAC LISANN, Primary Examiner. 

1. IN AN AIR GAUGE FOR CONTROLLING AIR BLEEDING IN A PNEUMATIC MEASURING CIRCUIT AND INCLUDING AN ELONGATED BODY HAVING A BORE, RADIAL AIR OUTLETS COMMUNICATING WITH THE BORE AND AN ELONGATED AIR INLET; A CYLINDRICAL AIR INLET BEARING IN SAID INLET COMMUNICATING WITH SAID BORE; A HOLLOW OPEN ENDED BEARING NUT PROJECTED INTO SAID BORE AT AND ENGAGING ONE END OF THE BODY; A WORK PIECE ENGAGING STEM AXIALLY MOUNTED WITHIN THE BODY AND ADJACENT ITS OPPOSITE ENDS GUIDABLY, SLIDABLY AND AXIALLY JOURNALLED RESPECTIVELY IN SAID INTAKE BEARING AND SAID BEARING NUT; THE IMPROVEMENT COMPRISING: AN AXIALLY MOVABLE SPRING BIASED NORMALLY CLOSED AUTOMATIC AIR SHUT-OFF VALVE OF CYLINDRICAL SHAPTE SNUGLY 